Research has shown that patients with insomnia often complain of impaired concentration, impaired memory, and decreased ability to accomplish daily tasks and that these factors worsen as their sleep problems increase in severity. Despite the evidence that insomnia exacts a significant toll on individuals, research has been equivocal as to objectively measured neuropsychological (NP) performance deficits. In this study, NP testing will be combined with functional MRI (FMRI) to investigate and assess cognitive performance in primary insomnia. The specific aims of his study are to: 1) compare patients with insomnia to matched controls on NP test performance, 2) compare patients with insomnia to matched controls on FMRI measures of brain function during cognitive challenges, and 3) examine the relationship between FMRI BOLD signal responses and objective and subjective measures of performance in patients with insomnia, to test whether hypothesized increases in activation represent compensatory responses similar to those observed with sleep deprivation. Avenues for future investigation may include studies of insomnia subtypes (e.g., subjective versus objective) and/or new approaches to treatment of insomnia. [unreadable] [unreadable] [unreadable]